Copper prices have risen above $14,000 per tonne due to supply tightening on multiple fronts, ANZ Research said in a Thursday report.

The export ban on copper concentrate by the Democratic Republic of Congo tightened the market, while copper concentrate production from producers such as Chile and Peru disappointed, with mining output falling in June. China's refined copper output fell 3% year-over-year to 1.1 million tonnes in June.

South American production is forecast to contract by 3% to 8.5 million tonnes within the year, marking a consecutive year of decline.

Tariff-driven metal flows into the US also continue to distort the global copper balance.

The squeeze pushed the cash-to-three-month futures spread to a multi-year high of $400 per tonne before it normalized to around $100 per tonne.

BHP Group's (ASX:BHP) shares fell 1% in recent trading on Thursday, while those of Rio Tinto (ASX:RIO) and Capstone Copper (ASX:CSC) rose 1%.